Screws showing hot on a dimmer switch.

[Kevin L. Luce]

I came across this yesterday and don't know what to think about it. This is a dimmer switch the slides up and down and has the on/off switch on the bottom. The screws were hot to the touch.

The screws are painted white.

Any thoughts?


I also included a picture of what it can look like when the drywall is not cut out so heat and cooling can be supplied to a room. This was a 7 year old house.

[Chuck Lambert]

Dimmer switches do run warm. However there may be too great of a load on that particular switch or the switch itself may be faulty. Either way IMHO it should be reported.

[Jeffrey Moore]

The dimmer switch will be hotter than others and the metal screws will conduct the heat more than the plastic might. With the info given I would wonder about correct wiring of the switch. What was the ambient temp and how long had the light been on? Did the wiring in the wall show up?

[Michael Larson]

Originally Posted by kluce

I came across this yesterday and don't know what to think about it. This is a dimmer switch the slides up and down and has the on/off switch on the bottom. The screws were hot to the touch.

The screws are painted white.

Any thoughts?


I also included a picture of what it can look like when the drywall is not cut out so heat and cooling can be supplied to a room. This was a 7 year old house.

Are they really that hot?

At 129 F you would feel it as hot.

104 F(40 C) is the max on metal surfaces for equipment standards with no "Hot Surface" warning label present.

There may be nothing wrong here but more info is needed.

If they did not feel obviously HOT, I would not call it out.

An actual temperature measurement is in order if you really want to know.

[Rick Maday]

Originally Posted by mlarson

Are they really that hot?

At 129 F you would feel it as hot.

If they did not feel obviously HOT, I would not call it out.

Originally Posted by kluce

The screws were hot to the touch.

Saw the same thing at my brother-in-laws house. Sliding dimmer was hot to touch. He said he wired it and "it's fine, been like that for over a year"

I would call it out.

[Darren Spencer]

Most likely a 600W dimmer, what is total Watts it is powering?

[Michael Larson]

Originally Posted by rmaday

Saw the same thing at my brother-in-laws house. Sliding dimmer was hot to touch. He said he wired it and "it's fine, been like that for over a year"

I would call it out.

Why?

Is there something wrong with it?

Sorry, I missed Kevins "hot to touch" comment(oops!) but an actual temp. measurement will tell what is needed.

[Rick Maday]

Originally Posted by mlarson

Why?

I've got a small blister from the one at my B-I-L's house. Hate to see that happen to a kid.

I'd love to see a data sheet or something about how hot they are actually supposed to get.

[Rick Maday]

Originally Posted by mlarson

If they did not feel obviously HOT, I would not call it out.

Since you qualified that you would not call it out if they did not feel obviously hot, why would you call it out (since they did feel hot)?

[Michael Larson]

Originally Posted by rmaday

I've got a small blister from the one at my B-I-L's house. Hate to see that happen to a kid.

I'd love to see a data sheet or something about how hot they are actually supposed to get.

Ouch!

For Kevin and your BIL.

Check the dimming capacity of the switch and compare it to the actual load being controlled.

Perhaps in both cases the circuit is over lamped and not a switch defect.

[Kevin L. Luce]

In general, I wouldn't think the manufacturer would designed something that would result in the screws being that hot (with proper installation and wiring of course). I'm actually going back to the house today so I'm planning on taking off the cover to see what readings I get today.

The temperature in the house was 68 degrees yesterday. I had the lights on high for about 20 minutes. This switch supplies power to 6 recess lights in the living room ceiling which are way to high to determine anything else. The buyer actually went to turn the lights off and felt one of the screws.

The good thing about this situation is one of the buyers father is an electrician.

I'll post any new findings later on tonight when I get back.

[Michael Larson]

Kevin, it may just need a higher wattage rated dimmer installed.

they run warm but running too hot and above ratings destroys them quickly.

600 watt dimmers are common but 1000 watt are available.

http://www.lutron.com/diva/?s=17000&t=17200

[Peter W. Bennett]

IMO, it's too hot. Can't predict time to failure or in this case, time to a fire.

[David A. Andersen]

The screws are painted white.

What is the significants in this?

[Kevin L. Luce]

Originally Posted by dandersen

What is the significants in this?

With infrared, bare metal can give you a wrong reading. With the Infrared camera, I'm actually reading the temperature of the paint that's on the screw.